Improvement in adjustable centre-square



lntd (States sient- '(itiiiii.

WILLIAM H. BROCK, OF BRIDGEPORT, CONNECTICUT, ASSIGNOR TO HIMSELF AND CHARLES H. HUNTOON, OF THE SAME PLACE.

Letters Patent No. 89,625, dated May 4, 1869.

-IMPROVEMENT IN ADJUSTABLE CENTRE-SQUARE.

The Schedule referred to in these Letters Patent and making part of the same.

To all whom it may concern Be it known that I, WILLIAM H. BROCK, of Bridgeport, in the county of Fairfield, and State of Connecticut, have invented anew Improvement in Machinists Square and I do hereby declare the following, when taken in connection with the accompanying drawings, and the letters of reference marked thereon, to be a full, clear, and exact description ot' the same, and which said drawings constitute part of this specification, and represent, in-

Figures l and 2, top views, the tongue in different positions.

This invention relates to an improvement in squares for machinists use, more particularly to what are known as centre-squares, the object being to adapt the square to various uses; and l The invention consists in making the tongue adjustable, so as to be set at different positions from the angle of the T.

The invention also consists in combining, with the tongue and T so arranged, a pointer upon leg of the T, to adapt the square to a still more extended use.

To enable others to make jand use my invention, I will fully describe the saine as illustrated in the accompanying drawings.

A B are the two legs of the T, formed into a right angle, in the usual manner for a centre-square.

Upon one 'of the legs B is arranged a guide, C, upon which a slide, D, is arranged to move freely on the. said guide, and xedin any given position by the setsrcrew E.

From the slide D extends the tongue F, at a right angle with Vthe outeredge of the guide C, and atfortyve degrees from either leg. Therefore, when the tongue is set at the angle as in iig. 1, the tongue and two legs A and B form a centre-square, -to be' used in like manner as are centre-squares of ordinary coustruction, the edge of the guide C forming a base for lthe perpendicular indicatedby the square for other purposes.

The square being thus adjustable, it may be set at any point from the angle ofthe two legs A and B, as l each angle of the block, will describe, successively, each' side' of the hole to be cut. 'Ihisadjustment will suggest other uses, and show the importance of the adjustable tongue. y

For still further adjustment and use, upon one leg, A, is a pointer, G, slotted, and secured bya set-screw, H, so that, when free, it may be turned freely, and set in any desired position, as in iig. 2. One illustration of the use of this arrangement may be given: It is desirable to space equally a bar. The first-.point being ascertained, the distance between that and the next known, the pointer G is set, as in fig. 2, Within that distance of the tongue. Then, placing the square so that the pointer rests at the irstline, the second point A and IB, at right angles to each other, the said legsV provided with a guide,0, to receive the base, D, of the tongue, the said tongue madefadj ustable, soas to be moved to or from the angle of the two legs, and at anvangle equallydividing the `angle of the two legs, all

substantially as set forth."

2. In combination with the subject-matter of the first clause, the pointer G, made adjustable, substantially as set forth.

WILLIAM' H. BROOK. Witnesses:

J oHN E. EARLE, A. J. TIBBI'rs. 

